DZ8 is the most frequently named factor in the 198. It appears in 75.8% of all cases — as primary, secondary, or present at score 5 or above. That number is the central argument of the entire framework. In three quarters of the corporate failures documented here, specific human decisions and behaviours at the leadership level were a meaningful causal factor in the death. The businesses didn't fail despite their leaders. They failed because of what their leaders did, or failed to do, at the specific moments that mattered.
The zone is named by its test: would a different leader, at the same company, at the same moment, likely have produced a different outcome? If yes, DZ8 scores high. This is the counterfactual that distinguishes human failure from structural failure. It is deliberately demanding. Vague management weakness doesn't qualify. The zone requires specificity: name the decision, name the person, explain why it was terminal.
DZ8 takes many forms — the autocrat who removed all dissent, the founder who couldn't separate personal conviction from market reality, the CEO who optimised for narrative rather than operations, the board that protected a leader past the point where protection was possible. What they share is that the failure was not inevitable. A different set of decisions, by a different person or team, would have produced a different company. The ceiling was human. It didn't have to be that low.